折腾了好久，终于好了，最后查日志，是null.sys损坏，他坏了也不提示。详见下面链接 https://developers.weixin.qq.com/community/minihome/article/doc/000ee4b8bfcee072932ef5d4156813

polyline: [{         points:[{latitude: 43.82663, longitude: 87.61688},{latitude: 43.82763, longitude: 87.61788}],         color: "#ff0000",         width: 4,         dottedLine: false       },       {         points:[{latitude: 43.82573, longitude: 87.61698},{latitude: 43.82773, longitude: 87.61758}],         color: "#0400ff",         width: 4,         dottedLine: false       }], 亲测可行！可以写无数段。